William Shakespeare knew well enough the frustrations of bringing up teenage children. “I would there were no age between sixteen and three-and-twenty,” he wrote in The Winter’s Tale. “For there is nothing in the between but getting wenches with child, wronging the ancientry, stealing, fighting.” Now parents have united online in annoyance at adolescents “wronging the ancientry”, posting pictures of their offspring ignoring their beautiful surroundings in favour of their mobile phone screens. It started with a tweet by the comedian David Baddiel, who shared a picture of his son, Ezra, 13, studying his phone while perched on a...